Schiffbau zeppelin gesellschaft mit beschrankter haftttng



Mar. '27, 1923.

-f.'-1GHT WEIGHT GIRDE R.

FILED JUNE 28, I920. 2 SHEETS-SHEET INVENTORI fludfiudm/ 1,449,721. K. ARNSTEIN.

Mar. 27, 1923.

LIGHT WEIGHT GIRDER.

HLEDJUNE 28, I920- 2 SHEETS-SHEET 2.

fix, d

1,449,721. K. ARNSTEIN.

Patented Mar. 27, 1923.

UNITED STATES PATENT OFFIQE- KARL ARNSTEIN, OF FRIEDRICHSHAFEN, GERMANY, ASSIGNOR TO THE FIRM LUFT- SCHIFFBAU ZEIPELIN GESELLSCHAFT MIT BESCHRANKTER HAFTUNG, OF FRIED- RICHSHAFEN, GERMANY.

LIGHT-WEIGHT GIRDER.

Application filed June 28, 1920. Serial No. 392,486.

(GRANTED UNDER THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 41 STAT. L, 1313.)

To all whom it may concern:

Be it known that I, KARL ARNsTEIN, a citizen of the Czechoslovakia Republic, residing at Friedrichshafen, Germany, have invented certain new and useful Improvements in Light-VVeight Girders (for which I have filed application in Germany, March 1, 1918), of which the following is a specification.

My present invention relates to articulated light weight girders such as are, for example, employed as longitudinal girders for the supporting planes of flying machines. Now constructional elements of this kind are expected, while having a great length and .comparatively low height, to produce a very slight bend, the smallest possible weight, and to be to a considerable extent proof against axial compression.

In the case of the hitherto known forms of articulated girders, the panel work isgenerally composedof a continuous tubular or else solid bar, which has to be bent or fiattened at the joints. Sometimes, too, stripshaped stays or trusses are also employed for this purpose, produced by rolling or drawing, which are throughout of equal width. In the first case, the stays will turn out to be heavy, and will have their strength impaired by subsequent deformation, In the second case, the attachment will prove particularly difiicult.

My present invention is intended to obviate these drawbacks by a special shaping given to said stays or trusses, as also by the peculiar method devised for their interconnection. The improved articulated lightweight girder therefore oomprises either channel-shaped or V-shaped girder cross sections filled in with stays or trusses arranged crosswise. 'In accordance with this invention, these single trusses are stamped of sheet metal and are suitably riveted at the joints. With the view to increasing the strength of the structure, the cross section of these stays embodies a flanged longitudinal groove. Besides this, they are correspondingly enlarged at the joints, so that rivet connections may be readily produced. As the stays are formed by a stamping process, they may be provided by a single working operation with any peculiar shape thatmay be desired for each particular case. Moreover, the single pairs of stays may be combined to form cross-shaped structures, and this in the most convenient manner imaginable even before they are riveted to the tie sections, so that the construction of the icloriplete girder will be very much simpli- This improved structure embodies a substantial advance over and above girders having sheet metal panel work structures, inasmuch as the radius of gyration is increased, and also because, owing to the interconnection of the drawn and the stamped stays or trusses, the extent of the bending stress is halved.

If now the intercrossed stays be alternately connected within and without to the flanged portions of the ties, then the trusses 'may be riveted to one another at the points bent off to a greater extent relatively to the other.

It will, however, at times appear of advantage to cause the stays to repeatedly in tersect or cross each other, in consequence of which the separate lengths subject to bending stresswill be still more reduced, since the stays which in accordance with the invention may be riveted to each other at the point of connection will be further shortened. According to the nature of the stress arising, this method of arrangement for the stays may, say. for example, in the case of box section girders, be restricted to the lateral portions thereof, or else all the walls may be composed of stays, repeatedly intercrossing each other, stamped out of sheet metal, having a cross section embodying a flanged longitudinal groove, and suitably enlarged at thepoints of connection.

Several forms of execution of the subject matter of this invention are disclosed by way of example in the accompanying drawings, in which:

Fig. 1 is a side view of a girder,

Fig. 2 a cross section, on an enlarged scale, through a pair of intercrossed stays along line 2-2 in Fig. 1, i

Fig. 5 a longitudinal section along line r r o.) in Fig. 3,

Fig. 6 a cross sectional view of the angular profile formation of a box-section.

girder,

Fig. 7 a side view of the same,

Fig. 8 a sectional view along line 3--3 in Fig. 7 as viewed from below,

Fig. 9 a sectional plan. view of the lower tie section along line li in Fig. 7, as viewed from above, and

. Fig. 10 a side view of a modified form of girder construction.

In the form of construction shown in Figs. 1 to5, the girder is composed of two thin chord bars a and b of angle-shaped section, onthe flanges of which there are riveted stays 0 arranged crosswise. Each of these intercrossings comprises two completely identical stays, of which always the one is riveted to the inside faces, and the other to the outside'faces of the chord flanges. Each stay 0 is provided with a through.- going longitudinal groove. In addition, each stay is enlarged at the centre, as also at the ends in the .manner of a shackle, or the like; Besides, the said stays are provided with a flange or beading extending across their two longitudinal ed es, while the two cross edges running para lel to the edges of the chords are not flanged. Owing to the rovision of the longitudinal groove, the central enlargement, and the edge flaning, each single stay is in any case already to a high degree secured against bending stresses. The strength of the structure is,

however, still more and substantially enhanced by the fact of the groove and the edge Hanging being turned away from the plane of symmetry in-the case of each inter crossed structure, and that owing to the fact of the tie flanges being but rather thin, the flat, central. stay sections may be riveted together without requiring the one or the other stay to be turned or bent down. I

Figs. ;6-10 disclose a box girder, the chord members of which have an angular profile formation. These latter are mutually connected by means of stays or intercrossed stay structures, In Fig. 6, a denotes the angular profile formatlon of the upper, and b that of the lower tie member. In Fig. 7, the intercrossed stay structures :3 are riveted to the chord members a and Z), respectively. In the arrangement accord ing to Fig. 8 the angular members a are interconnected by plain stays 03. Subject to Fig. 9, the angular chord members 6 are interconnected in a manner similar to that of the lateral walls of the girder, by .means of intercrossed stay structuresd.

For more convenience, the stays belonging to the lateral walls of the girder, which would otherwise be seen in section, are not shown in Figs. 8 and 9. I y

In these last-mentioned two forms of construction the intercrossed stay structures, respectively, the single stays, always comprise stays of like shape and character having a continuous longitudinal groove and a flanging at their longitudinal sides. At their extremities (in the case of the intercrossed structures also at the centre) the said stays are suitably enlarged to the form of a shackle, to render a rivet connection possible.

The form of construction shown in Fig. 10 relates to a comparatively high form of light girder, the stays of which are arranged so as to repeatedly intercross. In this ar rangeinent, the stays (Z are riveted to the I chords said stays being likewise provided with the through-going central groove, lateral flanges and shackle-like enlargements both at the extremities as also at all the points of intersection, for the purpose of rendering a rivet connection possible.

I claim 2- 1. A girder comprising two longitudinal elements or chords and two rows of panel rods, the ends of the rods of one row being fixed to one side of said chords, the ends of the rods of the other row to the other side, each rod of one row crossing a rod of the other row and being fixed thereto at the crossing point. 7

2. A girder comprising two longitudinal lements or chords and two rows of sheet metal panel. rods, the ends of the rods of one row being fixed to one side of said chords, the ends of the rods of the other row to the other side, each rod of one row crossing a rod of: the other row and being fixed thereto at the crossing point.

A. girder comprising two longitudinal elements or chords and tworows of longitudinally grooved sheet metal panel rods,

the ends of the rods of one row being fixed to one side of said chords, the ends of the rods of the other row .to the other side, each i rod of one row crossing a rod of the other row and being fixed thereto at the crossing point. t i

i. A girder comprising two longitudinal elements or chords and. tworows. of panel rods, the broadened ends of the rods of one row being fixed to one side of said'chords,

the broadened ends of the rods of the other row to the other side, each rod of one row ofone row crossing a rod of the other row and being fixed thereto at the crossing point.

6. A girder comprising two longitudinal elements or chords and two rows of panel rods, the broadened ends of the rods of one row being fixed to one side of said chords, the broadened ends of the rods of the other row to the other side in two places, each rod of one row crossing a rod of the other row and being fixed thereto at the crossing point in two places.

7. A girder comprising two longitudinal elements or chords and two rows of panel rods, the ends of the rods of one row being fixed to one side of said chords, the ends of the rods of the other row to the other side, each rod of one row crossingseveral rods of the other row and being fixed thereto at the crossing points.

8. A girder comprising two longitudinal elements or chords and two rows of sheet metal panel rods with partly beaded lateral edges, the ends of the rods of one row being fixed to one side of said chords, the ends of the rods of the other row to the other side, each rod of one row crossing a rod of the other row and being fixed thereto at the crossing point.

9. A girder comprising two longitudinal elements or chords and two rows of panel rods, the broadened ends of the rods of one row being fixed to one side of said chords,

the broadened ends of the rods of the other row to the other side, each rod having a broadened portion intermediate its ends and crossing a rod of the other row with the broadened portions coinciding and being fixed to one another in two places.

10. A girder comprising two longitudinal elements or chords and two rows of sheet metal panel rods with partly beaded lateral edges, the ends of the rods of one row being fixed to one side of said chords, the ends of the rods of the other row to the other side, each rod having a broadened portion intermediate its ends and crossing a rod of the other row with the broadened portions coinciding and being fixed to one another in two places.

11. A girder comprising two longitudinal elements or chords and two rows of panel rods, the broadened ends of the rods of one row being fixed to one side of said chords, the broadened ends of the rods of the other row to the other side, each row having several broadened portions intermediate its ends and crossing several rods of the other row with the broadened portions of the intercrossed rods coinciding and being fixed to one another in two places.

In testimony whereof I aflix my signature.

KARL ARNSTEIN. 

